ABSTRACT
The objective of this study was to investigate the postprandial response of leptin, an appetite-regulating hormone, to different macronutrient mixtures in Thai meals. A within-subject repeat measurement was performed. Two groups of healthy Thais (10 men and 10 women in each group) received a single meal of equal calories composed either a high carbohydrate, low fat, low protein diet (HC-LFLP, carbohydrate:fat:protein = 70%:15%:15%) or a low carbohydrate, high fat, high protein diet (LC-HFHP, carbohydrate:fat:protein = 20%:50%:30%). Fasting and 30-minute interval postprandial blood levels of leptin, insulin and glucose were measured for a 2-hour period. In comparison to the LC-HFHP meal, the HC-LFLP meal produced a greater increase in glucose and insulin levels, but halted leptin from decreasing. Postprandial leptin levels were suppressed by a LC-HFHP meal but not by a HC-LFLP meal. The reduced leptin in conjunction with lower glucose and insulin levels may encourage overeating in habitual LC-HFHP diet consumers.